Bidirectional data communications cable

ABSTRACT

A bidirectional data communications cable is disclosed. The cable includes first connector, second connector, and cable housing coupled to the first and second connectors. The first connector includes a controller configured to determine whether the first connector is connected to a data source or data sink. If connected to a data source, the controller configures a switch circuit to route a data signal from the data source to an optical modulator for modulating an optical signal for transmission from the first to the second connector via an optical fiber. If connected to a data sink, the controller configures the switch circuit to route a data signal from an optical demodulator to the data sink, the optical demodulator receiving an optical signal modulated with the data signal from the second connector via an optical fiber. The second connector is configured similar to the first connector. The cable housing encloses the optical fibers.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/685,951, filed on Apr. 14, 2015, entitled “Bidirectional DataCommunications Cable,” which, in turn, claims the benefit of the filingdate of Provisional Application Ser. No. 61/979,239, filed on Apr. 14,2014, and entitled “Bidirectional Consumer Active Optical Cable IC,”both of which are incorporated herein by reference.

FIELD

This disclosure relates generally to data communications cables, and inparticular, to a bidirectional data communications cable.

BACKGROUND

Next-generation consumer audio-visual cables, e.g., High DefinitionMultimedia Interface (HDMI), Digital Visual Interface (DVI), andDisplayPort will operate at data rates greater than 10 Gigabytes perseconds (Gb/s). This presents an ideal transition point for usingoptical fiber for the data channels. Optical fiber is a low-loss mediumcapable of high data rates, longer transmission distances, and lowerpower consumption (for extremely high speeds) in contrast with copperwire solutions. However, consumer active optical HDMI cables have beenunidirectional source to sink/display. As such, the ends of the cablesare not interchangeable.

Thus, a bidirectional data communications cable capable of transmittinghigh speed data, such as HDMI, DVI, and DisplayPort multimedia data andcontrol signaling, is disclosed herein.

SUMMARY

An aspect of the disclosure relates to a bidirectional datacommunications cable. The bidirectional data communications cablecomprises a first connector configured to mate with a correspondingconnector of a data source or a data sink. The first connectorcomprises: (1) a first controller configured to generate a first modesignal based on whether the first connector is connected to the datasource or the data sink; (2) a first modulator configured to modulate afirst optical signal with a first data signal from the data source basedon the first mode signal; (3) a first demodulator configured todemodulate a second optical signal to produce a second data signal basedon the first mode signal; and (4) a first switch circuit configured to:(a) route the first data signal from the data source to the firstmodulator based on the first mode signal indicating that the firstconnector is connected to the data source; and (b) route the second datasignal from the first demodulator to the data sink based on the firstmode signal indicating that the first connector is connected to the datasink.

The bidirectional data communications cable further comprises a secondconnector configured to mate with a corresponding connector of the datasource or the data sink. The second connector comprises: (1) a secondcontroller configured to generate a second mode signal based on whetherthe second connector is connected to the data source or the data sink;(2) a second modulator configured to modulate the second optical signalwith the second data signal from the data source based on the secondmode signal; (3) a second demodulator configured to demodulate the firstoptical signal to produce the first data signal based on the second modesignal; and (4) a second switch circuit configured to: (a) route thesecond data signal from the data source to the second modulator based onthe second mode signal indicating that the second connector is connectedto the data source; and (b) route the first data signal from the seconddemodulator to the data sink based on the second mode signal indicatingthat the second connector is connected to the data sink.

The bidirectional data communications cable further comprises a cablehousing at least partially enclosing: (1) a first set of one or moreoptical fibers for transmitting the first modulated optical signal fromthe first connector to the second connector; and (2) a second set of oneor more optical fibers for transmitting the second modulated opticalsignal from the second connector to the first connector.

Other embodiments or variants of the aforementioned communications cableare disclosed. Further, other aspects, advantages and novel features ofthe disclosure will become apparent from the following detaileddescription of the invention when considered in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a diagram of an exemplary bidirectional datacommunications cable in accordance with an aspect of the disclosure.

FIG. 2 illustrates a diagram of another exemplary bidirectional datacommunications cable in accordance with another aspect of thedisclosure.

FIG. 3 illustrates a diagram of yet another exemplary bidirectional datacommunications cable in accordance with another aspect of thedisclosure.

FIG. 4 illustrates a diagram of still another exemplary bidirectionaldata communications cable in accordance with another aspect of thedisclosure.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

FIG. 1 illustrates a diagram of an exemplary bidirectional datacommunications cable 100 in accordance with an aspect of the disclosure.The communications cable 100 comprises a first connector 110, a secondconnector 170, and a cable housing 140 having opposite ends mechanicallycoupled or attached to the first and second connectors 110 and 170,respectively.

Since the data communications cable 100 is bidirectional, both the firstand second connectors 110 and 170 are each configured to connect toeither a corresponding connector of a source of high speed data or acorresponding connector of a sink of high speed data. For instance, ifthe first connector 110 is connected to a high speed data source, thesecond connector 170 is connected to a high speed data sink. Conversely,if the second connector 170 is connected to a high speed data source,the first connector 110 is connected to a high speed data sink.

The high speed data may be multimedia data (e.g., audio/video data),such as those specified in the HDMI, DVI, DisplayPort, and otherstandards, as well as future standards. Examples of high speed datasources include digital video recorders (DVRs), optical disc players,multimedia distribution facilities, and others. Examples of high speeddata sinks include display monitors, television sets, projectors, DVRs,and others.

The high speed data are in the form of electrical digital signals. As anexample, the high speed data may be configured as transition-minimizeddifferential signaling (TMDS). For instance, the first and secondconnectors 110 and 170 may each be configured to receive or produce N+1number of parallel high speed differential signals D0+/D0−, D1+/D1−,D2+/D2− to DN+/DN− associated with the high speed data.

For clarity purposes, the differential signals D0+/D0− to DN+/DN− arereferred to as FDO+/FDO− to FDN+/FDN−, if they are sent from the firstconnector 110 to the second connector 170. The differential signalsD0+/D0 to DN+/DN are referred to as RDO+/RDO− to RDN+/RDN−, if they aresent from the second connector 170 to the first connector 110. As thedata communications cable 100 is bidirectional, the designations “F” and“R” are arbitrary, and do not imply a directional-dependentimplementation for the physical cable.

In the case where the first connector 110 is connected to a high speeddata source, the first connector 110 includes circuitry configured toconvert the high speed data electrical signals FD0+/FD0− to FDN+/FDN−into corresponding modulated optical signals for transmission to thesecond connector 170 by way of optical fibers F0 to FN situated withinthe cable housing 140, respectively. In the case where the firstconnector 110 is connected to a high speed data sink, the firstconnector 110 includes circuitry configured to convert modulated opticalsignals received from the second connector 170 by way of optical fibersR0 to RN situated within the cable housing 140 into high speed dataelectrical signals RD0+/RD0− to RDN+/RDN−, respectively.

Conversely, in the case where the second connector 170 is connected to ahigh speed data source, the second connector 170 includes circuitryconfigured to convert the high speed electrical signals RD0+/RD0− toRDN+/RDN− into optical signals for transmission to the first connector110 by way of optical fibers R0 to RN, respectively. In the case thatthe second connector 170 is connected to a high speed data sink, thesecond connector 170 includes circuitry configured to convert opticalsignals received from the first connector 110 by way of optical fibersF0 to FN to the high speed electrical signals FD0+/FD0− to FDN+/FDN−,respectively.

With reference to FIG. 1, the first connector 110 comprises a switchcircuit 112, a transmitter circuit 114, a laser source 116, a photodetector circuit 118, a receiver circuit 120, and a controller 122. Theswitch circuit 112 is configured to either receive or produce the highspeed electrical signals D0+/D0− to DN+/DN−, depending on whether it isconnected to a high speed data source or a high speed data sink.

The controller 122 determines whether the first connector 110 isconnected to the signal source or the signal sink based on an input. Forinstance, the input may be from a user interface, which allows a user toselect whether the first connector 110 is connected to a high speed datasource or sink. The input may also be detected signal activity atcontacts of the first connector 110, such as the contacts associatedwith signals D0+/D0− to DN+/DN− and/or with control signals discussedfurther herein with respect to another embodiment. The input may bedetected signal activity at the output of the receiver circuit 120and/or the photo detector circuit 118. The input may be a control signalreceived by way of the first and/or second connectors 110 and 170. Basedon the input, the controller 122 generates a mode signal DIR SEL forconfiguring the switch circuit 112 for receiving or producing high speedelectrical signals D0+/D0− to DN+/DN−.

More specifically, the switch circuit 112 comprises individual switchingcomponents SW00, SW01, SW02 to SW0N. Each of the switching components isconfigured as a differential pair of single-pole-double-throw switchingelements. The switching components SW00, SW01, SW02 to SW0N also includeports (e.g., the switch pole) coupled to contacts of the first connector110 associated with the high speed electrical signals D0+/D0−, D1+/D1−,D2+/D2− to DN+/DN−, respectively. The switching components SW00, SW01,SW02 to SW0N include outputs ports (e.g., the first switch throw)coupled to inputs of signal conditioning components TX-00, TX-01, TX-02to TX-0N of the transmitter circuit 114, respectively. Further, theswitching components SW00, SW01, SW02 to SW0N further include inputports (e.g., the second switch throw) coupled to outputs of signalconditioning components RX-00, RX-01, RX-02 to RX-0N of the receivercircuit 120, respectively.

If the controller 122 determines that the first connector 110 isconnected to a high speed data source, the controller 122 generates themode signal DIR SEL to configure switching components SW00, SW01, SW02to SW0N to couple the first connector contacts associated with signalsD0+/D0−, D1+/D1−, D2+/D2− to DN+/DN− with inputs of the signalconditioning components TX-00, TX-01, TX-02 to TX-0N of the transmittercircuit 114, respectively.

In such configuration, the signal conditioning components TX-00, TX-01,TX-02 to TX-0N of the transmitter circuit 114 receive the high speeddata differential electrical signals FD0+/FD0−, FD1+/FD1−, FD2+/FD2− toFDN+/FDN, respectively. The signal conditioning components TX-00, TX-01,TX-02 to TX-0N condition the signals FD0+/FD0−, FD1+/FD1−, FD2+/FD2− toFDN+/FDN− suitable for driving (modulating) individual lasers L-00,L-01, L-02 to L-0N of the laser source 116, respectively. In response tothe drive signals, the lasers L-00, L-01, L-02 to L-0N generatemodulated optical signals FO-0, FO-1, FO-2 to FO-N for transmission tothe second connector 170 by way of optical fibers F0, F1, F2 to FN,respectively.

If, on the other hand, the controller 122 determines that the firstconnector 110 is connected to a high speed data sink, the controller 122generates the mode signal DIR SEL to configure the switching componentsSW00, SW01, SW02 to SW0N to couple the first connector contactsassociated with differential signals D0+/D0−, D1+/D1−, D2+/D2− toDN+/DN− with the outputs of the signal conditioning components RX-00,RX-01, RX-02 to RX-0N of the receiver circuit 120, respectively.

In such case, individual photo detectors PD-00, PD-01, PD-02 to PD-0N ofthe photo detector circuit 118 receive modulated optical signals RO-0,RO-1, RO-2 to RO-N from the second connector 170 by way of opticalfibers R0, R1, R2 to RN situated within the cable housing 140,respectively. In response to the modulated optical signals RO-0, RO-1,RO-2 to RO-N, the photo detectors PD-00, PD-01, PD-02 to PD-0N generatecorresponding electrical signals, which are provided to the signalconditioning components RX-00, RX-01, RX-02 to RX-0N of the receivercircuit 120, respectively.

The signal conditioning components RX-00, RX-01, RX-02 to RX-0Ncondition the corresponding electrical signals into differential signalsRD0+/RD0, RD1+/RD1−, RD2+/RD2− to RDN+/RDN− in a format suitable for thehigh speed data sink, such as into TMDS signals required by many of theprotocols, such as HDMI, DVI, and DisplayPort.

As previously discussed, since the controller 122 has configured theswitch circuit 112 such that the switching components SW00, SW01, SW02to SW0N couple the first connector contacts to the respective outputs ofthe signal conditioning components RX-00, RX-01, RX-02 to RX-0N, thedifferential signals RD0+/RD0−, RD1+/RD1−, RD2+/RD2− to RDN+/RDN− arerouted to the contacts for providing them to the high speed data sink.

Again, since the high speed data communications cable 100 isbidirectional, the operations of the components of the second connector170 is effectively the same as the components of the first connector110. For the sake of completeness, the description of the components andoperations of the second connector 170 follows:

The second connector 170 comprises a switch circuit 172, a transmittercircuit 174, a laser source 176, a photo detector circuit 178, areceiver circuit 180, and a controller 182. The switch circuit 172 isconfigured to either receive or produce high speed electrical signalsD0+/D0− to DN+/DN−, depending on whether it is connected to a high speeddata source or sink.

The controller 182 determines whether the second connector 170 isconnected to the data source or the data sink based on an input. Forinstance, the input may be from a user interface, which allows a user toselect whether the second connector 170 is connected to a high speeddata source or sink. The input may also be detected signal activity atcontacts of the first connector 170, such as the contacts associatedwith signals D0+/D0− to DN+/DN− and/or with control signals discussedfurther herein with respect to another embodiment. The input may bedetected signal activity at the output of the receiver circuit 180and/or the photo detector circuit 178. The input may be a control signalreceived by way of the second and/or first connectors 170 and 110. Basedon the input, the controller 182 generates a mode signal DIR SEL(complementary of mode signal DIR SEL generated by controller 122 of thefirst connector 110) for configuring the switch circuit 172 forreceiving or producing the high speed data electrical signals D0+/D0− toDN+/DN−.

More specifically, the switch circuit 172 comprises individual switchingcomponents SW10, SW11, SW12 to SW1N. Each of the switching components isconfigured as a differential pair of single-pole-double-throw switchingelements. The switching components SW10, SW11, SW12 to SW1N includeports (e.g., the switch pole) coupled to contacts of the secondconnector 170 associated with high speed electrical signals D0+/D0−,D1+/D1−, D2+/D2− to DN+/DN−, respectively. The switching componentsSW10, SW11, SW12 to SW1N also include outputs ports (e.g., the firstswitch throw) coupled to inputs of signal conditioning components TX-10,TX-11, TX-12 to TX-1N of the transmitter circuit 174, respectively.Further, the switching components SW10, SW11, SW12 to SW1N also includeinput ports (e.g., the second switch throw) coupled to outputs of signalconditioning components RX-10, RX-11, RX-12 to RX-1N of the receivercircuit 180, respectively.

If the controller 182 determines that the second connector 170 isconnected to a high speed data source, the controller 182 generates themode signal DIR SEL to configure the switching components SW10, SW11,SW12 to SW1N to couple the second connector contacts associated withsignals D0+/D0−, D1+/D1−, D2+/D2− to DN+/DN− to inputs of the signalconditioning components TX-10, TX-11, TX-12 to TX-1N of the transmittercircuit 174, respectively.

In such configuration, the signal conditioning components TX-10, TX-11,TX-12 to TX-1N receive the high speed differential signals RD0+/RD0−,RD1+/RD1−, RD2+/RD2− to RDN+/RDN−, respectively. The signal conditioningcomponents TX-10, TX-11, TX-12 to TX-1N condition the signals RD0+/RD0−,RD1+/RD1−, RD2+/RD2− to RDN+/RDN− suitable for driving (modulating)individual lasers L-10, L-11, L-12 to L-1N of the laser source 176,respectively. In response to the respective drive signals, the lasersL-10, L-11, L-12 to L-1N generate modulated optical signals RO-0, RO-1,RO-2 to RD-N for transmission to the first connector 110 by way ofoptical fibers RO, R1, R2 to RN, respectively.

If, on the other hand, the controller 182 determines that the secondconnector 170 is connected to a high speed data sink, the controller 182generates the mode signal DIR SEL to configure the switching componentsSW10, SW11, SW12 to SW1N to couple the second connector contactsassociated with signals D0+/D0−, D1+/D1−, D2+/D2− to DN+/DN− with theoutputs of the signal conditioning components RX-10, RX-11, RX-12 toRX-1N of the receiver circuit 180, respectively.

In such case, individual photo detectors PD-10, PD-11, PD-12 to PD-1N ofthe photo detector circuit 178 receive modulated optical signals FO-0,FO-1, FO-2 to FO-N from the first connector 110 by way of optical fibersF0, F1, F2 to FN, respectively. In response to the modulated opticalsignals FO-0, FO-1, FO-2 to FO-N, the photo detectors PD-10, PD-11,PD-12 to PD-1N generate corresponding electrical signals, which areprovided to the signal conditioning components RX-10, RX-11, RX-12 toRX-1N of the receiver circuit 180, respectively. The signal conditioningcomponents RX-10, RX-11, RX-12 to RX-1N condition the correspondingelectrical signals to generate differential signals FD0+/FD0−,FD1+/FD1−, FD2+/FD2− to FDN+/FDN− in a format suitable for the highspeed data sink, such as into TMDS signals required by many of theprotocols, such as HDMI, DVI, and DisplayPort.

As previously discussed, since the controller 182 has configured theswitch circuit 172 such that the switching components SW10, SW11, SW12to SW1N couple the second connector contacts to the respective outputsof the signal conditioning components RX-10, RX-11, RX-12 to RX-1N, thesignals FD0+/FD0−, FD1+/FD1−, FD2+/FD2− to FDN+/FDN− are routed to thecontacts for providing them to the high speed data sink.

FIG. 2 illustrates a diagram of another exemplary bidirectional datacommunications cable 200 in accordance with another aspect of thedisclosure. The data communications cable 200 is similar to that ofcable 100 previously discussed, and includes many of the same or similarelements as indicated by the same reference numbers, with the exceptionthat the most significant digit is a “2” rather than a “1”. The datacommunications cable 200 differs from cable 100 in that cable 200comprises multiplexers (MUX) and de-multiplexers (DEMUX) formultiplexing and de-multiplexing data signals. The multiplexed datasignals are used for modulating one or more optical signals fortransmission from the first connector to the second connector orvice-versa, and the de-multiplexed data signals are generated at thereceiving connector from the one or more modulated optical signals. Suchconfiguration allows for a reduction in the number of optical fibersrequired for the data communications cable 200.

In particular, the data communications cable 200 comprises an inputconnector 210, a cable housing 240, and a second connector 270. Thecable housing 240 includes opposite ends mechanically coupled orattached to the first and second connectors 210 and 270, respectively.The cable housing 240 protectively encloses an optical fiber F fortransmitting an optical signal FO from the first connector 210 to thesecond connector 270. Additionally, the cable housing 240 protectivelyencloses another optical fiber R for transmitting an optical signal ROfrom the second connector 270 to the first connector 110.

The first connector 210 comprises a switch circuit 212, a transmittercircuit 214, a multiplexer (MUX) 224, and a laser source 226. The firstconnector 210 further comprises a photo detector (PD) 228, ade-multiplexer (DEMUX) 230, a receiver circuit 220, and a controller222.

As in the previous embodiment, the controller 222 detects whether thefirst connector 210 is connected to a high speed data source or a highspeed data sink based on an input. In response to such detection, thecontroller 222 generates a mode signal DIR SEL for configuring theswitch circuit 212.

If the controller 222 detects that the first connector 210 is connectedto a high speed data source, the controller 222 generates the DIR SELmode signal to configure switching components SW00, SW01, SW02 to SW0Nto couple the first connector contacts associated with differentialsignals D0+/D0−, D1+/D1, D2+/D2− to DN+/DN− to inputs of signalconditioning components TX-00, TX-01, TX-02 to TX-0N of the transmittercircuit 214, respectively. As in the previous embodiment, the signalconditioning components TX-00, TX-01, TX-02 to TX-0N generateappropriate drive signals for driving (modulating) the laser source 226based on the differential signals FD0+/FD0−, FD1+/FD1−, FD2+/FD2− toFDN+/FDN−, respectively.

The drive signals generated by the signal conditioning components TX-00,TX-01, TX-02 to TX-0N of the transmitter circuit 214 are sent to the MUX224. The MUX 224 multiplexes the drive signals onto a pair ofdifferential lines coupled to the laser source 226. The laser source 226modulates the multiplexed differential signals FD0+/FD0−, FD1+/FD1−,FD2+/FD2− to FDN+/FDN− onto an optical signal FO for transmission to thesecond connector 270 by way of the optical fiber F.

If the controller 222 detects that the first connector 210 is connectedto a high speed data sink, the controller 222 generates the DIR SEL modesignal to configure the switching components SW00, SW01, SW02 to SW0N ofthe switch circuit 212 to couple the first connector contacts associatedwith differential signals D0+/D0−, D1+/D1−, D2+/D2− to DN+/DN− tooutputs of signal conditioning components RX-00, RX-01, RX-02 to RX-0Nof the receiver circuit 220, respectively.

In this case, the photo detector (PD) 228 receives a modulated opticalsignal RO from the second connector 270 by way of optical fiber R. Theoptical signal RO is modulated with a multiplexed differential signalRD0+/RD0−, RD1+/RD1−, RD2+/RD2− to RDN+/RDN−. In response to the opticalsignal RO, the photo detector 228 generates the correspondingmultiplexed differential electrical signal. The DEMUX 230 de-multiplexesthe multiplexed differential electrical signal, and provides thedemultiplexed signals to the receiver circuit 220.

The signal conditioning components RX-00, RX-01, RX-02 to RX-0N of thereceiver circuit 220 condition the corresponding demultiplexeddifferential signals to generate the differential signal RD0+/RD0−,RD1+/RD1−, RD2+/RD2− to RDN+/RDN− in a format suitable for the highspeed data sink, such as into TMDS signals required by many of theprotocols, such as HDMI, DVI, and DisplayPort.

As previously discussed, since the controller 222 has configured theswitch circuit 212 such that the switching components SW00, SW01, SW02to SW0N couple the first connector contacts to the respective outputs ofthe signal conditioning components RX-00, RX-01, RX-02 to RX-0N of thereceiver circuit 220, the signals RD0+/RD0−, RD1+/RD1−, RD2+/RD2− toRDN+/RDN− are routed to the contacts for providing them to the highspeed data sink.

Again, since the high speed data communications cable 200 isbidirectional, the operations of the components of the second connector270 is effectively the same as the components of the first connector210. For the sake of completeness, the description of the components andoperations of the second connector 270 follows:

The second connector 270 comprises a switch circuit 272, a transmittercircuit 274, a multiplexer (MUX) 284, and a laser source 286. The secondconnector 270 further comprises a photo detector (PD) 288, ade-multiplexer (DEMUX) 290, a receiver circuit 280, and a controller282.

As in the previous embodiment, the controller 282 detects whether thesecond connector 270 is connected to a high speed data source or a highspeed data sink based on an input. In response to such detection, thecontroller 282 generates a mode signal DIR SEL for configuring theswitch circuit 272.

If the controller 282 detects that the second connector 270 is connectedto a high speed data source, the controller 282 generates the DIR SELmode signal to configure switching components SW10, SW11, SW12 to SW1Nto couple the second connector contacts associated with differentialsignals D0+/D0, D1+/D1−, D2+/D2− to DN+/DN− to inputs of signalconditioning components TX-10, TX-11, TX-12 to TX-1N of the transmittercircuit 274, respectively. As in the previous embodiment, the signalconditioning components TX-10, TX-11, TX-12 to TX-1N generateappropriate drive signals for driving (modulating) the laser source 286based on the differential signals RD0+/RD0−, RD1+/RD1−, RD2+/RD2− toRDN+/RDN−, respectively.

The drive signals generated by the signal conditioning components TX-10,TX-11, TX-12 to TX-1N of the transmitter circuit 274 are sent to the MUX284. The MUX 284 multiplexes the drive signals onto a pair ofdifferential lines coupled to the laser source 286. The laser source 286modulates the multiplexed differential signals RD0+/RD0−, RD1+/RD1−,RD2+/RD2− to RDN+/RDN− onto an optical signal RO for transmission to thefirst connector 210 by way of the optical fiber R.

If the controller 282 detects that the second connector 270 is connectedto a high speed data sink, the controller 282 generates the DIR SEL modesignal to configure the switching components SW10, SW11, SW12 to SW1N ofthe switch circuit 272 to couple the second connector contactsassociated with differential signals D0+/D0−, D1+/D1−, D2+/D2− toDN+/DN− to outputs of signal conditioning components RX-10, RX-11, RX-12to RX-1N of the receiver circuit 280, respectively.

In this case, the photo detector 288 receives a modulated optical signalFO from the first connector 210 by way of optical fiber F. The opticalsignal FO is modulated with multiplexed differentials signals FD0+/FD0−,FD1+/FD1−, FD2+/FD2− to FDN+/FDN−. In response to the optical signal FO,the photo detector 288 generates the multiplexed differential electricalsignals. The DEMUX 290 de-multiplexes the multiplexed differentialsignals, and provides the demultiplexed signals to the receiver circuit280.

The signal conditioning components RX-10, RX-11, RX-12 to RX-1Ncondition the corresponding demultiplexed electrical signals intodifferential signals FD0+/FD0−, FD1+/FD1−, FD2+/FD2− to FDN+/FDN− in aformat suitable for a high speed data sink, such as into TMDS signalsrequired by many of the protocols, such as HDMI, DVI, and DisplayPort.

As previously discussed, since the controller 282 has configured theswitch circuit 272 such that the switching components SW10, SW11, SW12to SW1N couple the second connector contacts to the respective outputsof the signal conditioning components RX-10, RX-11, RX-12 to RX-1N, thesignals FD0+/FD0−, FD1+FD1−, FD2+/FD2− to FDN+/FDN− are routed to thecontacts for providing them to the high speed data sink.

Although in exemplary data communications cable 200, the correspondingMUX multiplexed the differential signals for transmission via a singleoptical fiber, it shall be understood that the cable 200 may comprise aplurality of MUXs to multiplex respective subsets of the differentialsignals for transmission by way of corresponding optical fibers. In suchcase, the data communications cable 200 may comprise a plurality ofDEMUX to demultiplex respective subsets of the differential signalsreceived by way of corresponding optical fibers.

FIG. 3 illustrates an exemplary bidirectional data communications cable300 in accordance with another aspect of the disclosure. As previouslydiscussed, the data communications cables described herein may beconfigured for HDMI, DVI, and Display Port applications. In suchapplications, the data communications cables facilitate the transmissionof not only the high speed multimedia (e.g., audio/video) data, but alsoassociated control signaling (e.g., control data and/or clock).

For example, HDMI has the SDA, SCL, and CEC controls signals that aretypically transmitted with the high speed multimedia data. DisplayPorthas the auxiliary positive and negative signals AUX+ and AUX− that aretypically transmitted with the high speed multimedia data. And, DVI hascontrol signal and clock DDC Data and DDC CLK that are typicallytransmitted with the high speed multimedia data.

With reference to FIG. 3, the data communications cable 300 comprises afirst connector 310, a cable housing 340, and a second connector 370.The cable housing 340 includes opposite ends mechanically coupled orattached to the first and second connectors 310, and 370, respectively.

The cable housing 340 protectively encloses one or more optical fibers Ffor transmission of modulated optical signals from the first connector310 to the second connector 370, encloses one or more other opticalfibers R for transmission of modulated optical signals from the secondconnector 370 to the first connector 310, and one or more wires fortransmitting low-speed control signals (e.g., data and/or clock) betweenthe first and second connectors 310 and 370.

The first connector 310 comprises a switch circuit 312, a transmittercircuit 314, a laser with optional multiplexer 316, a photo detectorwith optional demultiplexer 318, a receiver circuit 320, and acontroller 322. Additionally, the first connector 310 comprises abidirectional transceiver 330.

Similar to the previous embodiments, the controller 322 determineswhether the first connector 310 is connected to a high speed multimediadata source or a high speed multimedia data sink based on an input. Theinput may include: (1) a user input by way of a user interface (e.g., ahard or soft switch); (2) detected signal activity on any of thecontacts of the first and/or second connectors 310 and 370, such ascontacts associated with the high speed data D0+/D0− to DN+/DN− and/orthe contacts associated with the low-speed control signals C0 to CM; (3)a control signal received from control signal contacts C0 to CM of thefirst or second connector 310 or 370; and (4) other inputs.

If the controller 322 determines that the first connector 310 isconnected to a high speed data source, the controller 322 generates amode signal DIR SEL to configure the switch circuit 312 to route thehigh speed data electrical signaling received from the source via firstconnector contacts associated with data signals D0+/D0− to DN+/DN− tothe transmitter circuit 314. The transmitter circuit 314, in turn,conditions the data signaling for driving (modulating) the laser source316.

If the data communications cable 300 is configured similar to cable 100of FIG. 1 (i.e., there is no multiplexer), the laser source 316generates modulated optical data signals for transmission by way ofcorresponding optical fibers F. If the data communications cable 300 isconfigured similar to cable 200 of FIG. 2, one or more multiplexermultiplexes the high speed data signals for driving (modulating)corresponding one or more laser sources. The one or more laser sources316 generate corresponding one or more modulated optical signals FO fortransmission to the second connector 370 by way of the one or moreoptical fibers F, respectively.

If the controller 322 determines that the first connector 310 isconnected to a high speed data sink, the controller 322 generates a modesignal DIR SEL to configure the switch circuit 312 to route high speeddata electrical signaling generated by the receiver circuit 320 to thehigh speed data sink via the first connector contacts associated withdata signals D0+/D0− to DN+/DN−.

In such case, the photo detector circuit 318 receives one or moremodulated optical signals RO by way of one or more optical fibers R,respectively. If the data communications cable 300 is configured similarto cable 100 of FIG. 1 (e.g., does not include a DEMUX), the photodetector circuit 318 generates corresponding electrical signals inresponse to the modulated optical signals. If the data communicationscable 300 is configured similar to cable 200 of FIG. 2 (includes one ormore DEMUXs), the photo detector circuit 318 with the one or more DEMUXsgenerate corresponding high speed data electrical signals in response toone or more modulated optical signals, respectively.

The receiver circuit 320 conditions the corresponding high speed dataelectrical signals received from the photo detector circuit 318 in asuitable format for a high speed data sink. The switch circuit 312routes the conditioned high speed data signals from the receiver circuit320 to the high speed data sink connected to the first connector 310.

The transceiver 330 receives low-speed control signals (e.g., dataand/or clock) from a device (high speed data source or sink) by way ofcontacts of the first connector 310 associated with signaling C0 to CM.The transceiver 330 configures the signaling for transmission to thesecond connector 370 by way of one or more wires. Similarly, thetransceiver 330 receives low-speed control signals (e.g., data and/orclock) from the second connector 370 by way of the one or more wires,and configures the received signaling for providing to the device (highspeed data source or sink) by way of contacts of the first connector 310associated with signaling C0 to CM.

Since the data communications cable 300 is bidirectional, the operationsof the components of the second connector 370 is effectively the same asthe components of the first connector 310. For the sake of completeness,the description of the components and operations of the second connector370 follows:

The second connector 370 comprises a switch circuit 372, a transmittercircuit 374, a laser with optional multiplexer 376, a photo detectorwith optional demultiplexer 378, a receiver circuit 380, and acontroller 382. Additionally, the second connector 370 comprises abidirectional transceiver 390.

Similar to the previous embodiments, the controller 382 determineswhether the second connector 370 is connected to a high speed multimediadata source or a high speed multimedia data sink based on an input. Theinput may include: (1) a user input by way of a user interface (e.g., ahard or soft switch); (2) detected signal activity on any of thecontacts of the second and/or first connectors 370 and 310, such ascontacts associated with the high speed data D0+/D0− to DN+/DN− and/orthe contacts associated with the low-speed control signals C0 to CM; (3)a control signal from the control signals contact C0 to CM of the secondor first connector 370 or 310; and (4) other inputs.

If the controller 382 determines that the second connector 370 isconnected to a high speed data source, the controller 372 generates amode signal DIR SEL to configure the switch circuit 372 to route thehigh speed data electrical signaling received from the source via secondconnector contacts associated with data signals D0+/D0− to DN+/DN− tothe transmitter circuit 374. The transmitter circuit 374, in turn,conditions the data signaling for driving (modulating) the laser source376.

If the data communications cable 300 is configured similar to cable 100of FIG. 1 (i.e., there is no multiplexer), the laser source 376generates modulated optical data signals for transmission by way ofcorresponding optical fibers F. If the data communications cable 300 isconfigured similar to cable 200 of FIG. 2, one or more multiplexersmultiplexes the high speed data signals for driving (modulating)corresponding one or more laser sources 316. The one or more lasersources 316 generate corresponding one or more modulated optical signalsRO for transmission to the first connector 310 by way of the one or moreoptical fibers R, respectively.

If the controller 382 determines that the second connector 370 isconnected to a high speed data sink, the controller 382 generates a modesignal DIR SEL to configure the switch circuit 372 to route high speeddata electrical signaling generated by the receiver circuit 380 to thehigh speed data sink via the second connector contacts associated withdata signals D0+/D0− to DN+/DN−.

In such case, the photo detector circuit 378 receives one or moremodulated optical signals FO by way of one or more optical fibers F,respectively. If the data communications cable 300 is configured similarto cable 100 of FIG. 1 (e.g., does not include a DEMUX), the photodetector circuit 378 generates corresponding electrical signals inresponse to the modulated optical signals. If the data communicationscable 300 is configured similar to cable 200 of FIG. 2 (includes one ormore DEMUXs), the photo detector circuit 378 with the one or more DEMUXsgenerate corresponding high speed data electrical signals in response toone or more modulated optical signals.

The receiver circuit 380 conditions the corresponding high speed dataelectrical signals received from the photo detector circuit 378 in asuitable format for a high speed data sink. The switch circuit 372routes the conditioned high speed data signals from the receiver circuit380 to the high speed data sink connected to the second connector 370.

The transceiver 390 receives low-speed control signals (e.g., dataand/or clock) from a device (high speed data source or sink) by way ofcontacts of the second connector 370 associated with signaling C0 to CM.The transceiver 390 configures the signaling for transmission to thefirst connector 310 by way of one or more wires. Similarly, thetransceiver 390 receives low-speed control signals (e.g., data and/orclock) from the first connector 310 by way of the one or more wires, andconfigures the received signaling for providing to the device (highspeed data source or sink) by way of contacts of the second connector370 associated with signaling C0 to CM.

FIG. 4 illustrates another exemplary bidirectional data communicationscable 400 in accordance with another aspect of the disclosure. The datacommunications cable 400 is similar to that of cable 300 previouslydiscussed, and includes many of the same or similar elements asindicated by the same reference numbers, except the most significantdigit is a “4” rather than a “3”. The data communications cable 400differs from cable 300 in that the first and second connectors compriserespective transceivers for transmitting the low speed signaling betweenthe connectors by way of one or more optical fibers. As such, the datacommunications cable may be implemented exclusively with optical fibersas the transmission medium.

In particular, the data communications cable 400 comprises a firstconnector 410, a cable housing 440, and a second connector 470. Thecable housing 440 protectively encloses one or more optical fibers F fortransmitting high speed data from the first connector 410 to the secondconnector 470, one or more optical fibers R for transmitting high speeddata from the second connector 470 to the first connector 410, and oneor more optical fibers for transmitting low speed control signals (e.g.,data and/or clock) between the first and second connectors 410 and 470.

The first connector 410 comprises a switch circuit 412, a transmittercircuit 414, a laser source with optical multiplexer 416, a photodetector circuit 418, a receiver circuit 420, and a controller 422.These components of the first connector 410 are the same as those of thefirst connector 310 of cable 300 for transmitting high speed data fromthe first connector to the second connector, and vice-versa.Accordingly, the detailed description of the components 412, 414, 416,418, 420, and 422 has been provided herein.

The first connector 410 further comprises a transceiver 435 fortransmitting and receiving low speed control signals to and from thefirst and second connectors 410 and 470 by way of one or more opticalfibers. Accordingly, the transceiver 435 may receive low speed controlsignals from a device (e.g., high speed data source or sink) by way offirst connector contacts C0 to CM, and generate one or more opticalsignals modulated (and optionally multiplexed) with the low speedcontrol signals for transmission to the second connector 470.Additionally, the transceiver 435 may receive one or more opticalsignals modulated (and optionally multiplexed) with the low speedcontrol signals from the second connector 470, and demodulate (andoptionally demultiplexed) the one or more optical signals to provide thelow speed control signals to the device (e.g., high speed data source orsink) by way of the first connector contacts C0 to CM.

The second connector 470 comprises a switch circuit 472, a transmittercircuit 474, a laser source with optical multiplexer 476, a photodetector circuit 478, a receiver circuit 480, and a controller 482.These components of the second connector 470 are the same as those ofthe second connector 370 of cable 300 for transmitting high speed datafrom the second connector to the first connector, and vice-versa.Accordingly, the detailed description of the components 472, 474, 476,478, 480, and 482 has been provided herein.

The second connector 470 further comprises a transceiver 495 fortransmitting and receiving low speed control signals between the secondand first connectors 470 and 410 by way of one or more optical fibers.Accordingly, the transceiver 495 may receive low speed control signalsfrom a device (e.g., high speed data source or sink) by way of secondconnector contacts C0 to CM, and generate one or more optical signalsmodulated (and optionally multiplexed) with the low speed controlsignals for transmission to the first connector 410. Additionally, thetransceiver 495 may receive one or more optical signals modulated (andoptionally multiplexed) with the low speed control signals from thefirst connector 410, and demodulate (and optionally demultiplexed) theone or more optical signals to provide the low speed control signals tothe device (e.g., high speed data source or sink) by way of the secondconnector contacts C0 to CM.

While the invention has been described in connection with variousembodiments, it will be understood that the invention is capable offurther modifications. This application is intended to cover anyvariations, uses or adaptation of the invention following, in general,the principles of the invention, and including such departures from thepresent disclosure as come within the known and customary practicewithin the art to which the invention pertains.

What is claimed is:
 1. A bidirectional data communications cable,comprising: a first connector configured to mate with a correspondingconnector of a data source or a data sink; a first modulator configuredto modulate a first optical signal with a first data signal if the firstconnector is mated with the corresponding connector of the data source;a first demodulator configured to demodulate a second optical signal toproduce a second data signal if the first connector is mated with thecorresponding connector of the data sink; a first switch circuitconfigured to: route the first data signal from the data source to thefirst modulator if the first connector mated with the correspondingconnector of the data source; and route the second data signal from thefirst demodulator to the data sink if the first connector is connectedto the corresponding connector of the data sink; a second connectorconfigured to mate with a corresponding connector of the data source orthe data sink; a second modulator configured to modulate the secondoptical signal with the second data signal if the second connector ismated with the corresponding connector of the data source; a seconddemodulator configured to demodulate the first optical signal to producethe first data signal if the second connector is mated with thecorresponding connector of the data sink; a second switch circuitconfigured to: route the second data signal from the data source to thesecond modulator if the second connector is mated with the correspondingconnector of the data source; and route the first data signal from thesecond demodulator to the data sink if the second connector is matedwith the corresponding connector of the data sink; and a first set ofone or more optical fibers for transmitting the first modulated opticalsignal from the first connector to the second connector; and a secondset of one or more optical fibers for transmitting the second modulatedoptical signal from the second connector to the first connector.
 2. Thebidirectional data communications cable of claim 1, further comprising acontroller configured to: determine whether the first connector isconnected to the data source or the data sink; and configure the firstswitch circuit based on said determination.
 3. The bidirectional datacommunications cable of claim 2, wherein the controller is configured todetermine whether the first connector is connected to the data source orthe data sink based on a user input.
 4. The bidirectional datacommunications cable of claim 2, wherein the controller is configured todetermine whether the first connector is connected to the data source orthe data sink based on signal activity at one or more contacts of thefirst connector, at one or more contacts of the second connector, or atboth the one or more contacts of the first connector and the one or morecontacts of the second connector.
 5. The bidirectional datacommunications cable of claim 2, wherein the controller is configured todetermine whether the first connector is connected to the data source orthe data sink based on a control signal received by way of one or morecontacts of the first connector, one or more contacts of the secondconnector, or both the one or more contacts of the first connector andthe one or more contacts of the second connector.
 6. The bidirectionaldata communications cable of claim 1, wherein the first modulatorcomprises: a transmitter circuit configured to generate a modulatingsignal based on the first data signal; and a laser source configured togenerate the first modulated optical signal based on the modulatingsignal.
 7. The bidirectional data communications cable of claim 1,wherein the first modulator comprises: a transmitter circuit configuredto generate a modulating signal based on the first data signal; amultiplexer configured to generate a multiplexed modulating signal basedon the modulating signal; and a laser source configured to generate thefirst modulated optical signal based on the multiplexed modulatingsignal.
 8. The bidirectional data communications cable of claim 1,wherein the first demodulator comprises: a photo detector circuitconfigured to generate an electrical signal based on the secondmodulated optical signal; and a receiver circuit configured to generatethe second data signal based on the electrical signal.
 9. Thebidirectional data communications cable of claim 1, wherein the firstdemodulator comprises: a photo detector circuit configured to generatean electrical signal based on the second modulated optical signal; ademultiplexer configured to generate a demultiplexed signal based on theelectrical signal; and a receiver circuit configured to generate thesecond data signal based on the demultiplexed signal.
 10. Thebidirectional data communications cable of claim 1, further comprising acontroller is configured to: determine whether the second connector isconnected to the data source or the data sink; and configure the secondswitch circuit based on said determination.
 11. The bidirectional datacommunications cable of claim 10, wherein the controller is configuredto determine whether the second connector is connected to the datasource or the data sink based on a user input.
 12. The bidirectionaldata communications cable of claim 10, wherein the controller isconfigured to determine whether the second connector is connected to thedata source or the data sink based on signal activity at one or morecontacts of the second connector, at one or more contacts of the firstconnector, or at both the one or more contacts of the second connectorand the one or more contacts of the first connector.
 13. Thebidirectional data communications cable of claim 10, wherein thecontroller is configured to determine whether the second connector isconnected to the data source or the data sink based on a control signalreceived by way of one or more contacts of the second connector, one ormore contacts of the first connector, or both the one or more contactsof the second connector and the one or more contacts of the firstconnector.
 14. The bidirectional data communications cable of claim 1,wherein the second modulator comprises: a transmitter circuit configuredto generate a modulating signal based on the second data signal; and alaser source configured to generate the second modulated optical signalbased on the modulating signal.
 15. The bidirectional datacommunications cable of claim 1, wherein the second modulator comprises:a transmitter circuit configured to generate a modulating signal basedon the second data signal; a multiplexer configured to generate amultiplexed modulating signal based on the modulating signal; and alaser source configured to generate the second modulated optical signalbased on the multiplexed modulating signal.
 16. The bidirectional datacommunications cable of claim 1, wherein the second demodulatorcomprises: a photo detector circuit configured to generate an electricalsignal based on the first modulated optical signal; and a receivercircuit configured to generate the first data signal based on theelectrical signal.
 17. The bidirectional data communications cable ofclaim 1, wherein the second demodulator comprises: a photo detectorcircuit configured to generate an electrical signal based on the firstmodulated optical signal; a demultiplexer configured to generate ademultiplexed signal based on the electrical signal; and a receivercircuit configured to generate the first data signal based on thedemultiplexed signal.
 18. The bidirectional data communications cable ofclaim 1, further comprising: one or more wires; and a transceiverconfigured to: receive a first control signal from the data source orthe data sink by way of one or more contacts of the first connector;generate a first transmit signal based on the first control signal fortransmission to the second connector by way of the one or more wires;receive a second transmit signal from the second connector by way of theone or more wires; and generate a second control signal based on thesecond transmit signal for providing to the data source or the data sinkby way of the one or more contacts of the first connector.
 19. Thebidirectional data communications cable of claim 1, further comprising:one or more wires; and a transceiver configured to: receive a firstcontrol signal from the data source or the data sink by way of one ormore contacts of the second connector; generate a first transmit signalbased on the first control signal for transmission to the firstconnector by way of the one or more wires; receive a second transmitsignal from the first connector by way of the one or more wires; andgenerate a second control signal based on the second transmit signal forproviding to the data source or the data sink by way of the one or morecontacts of the second connector.
 20. The bidirectional datacommunications cable of claim 1, further comprising: a third set of oneor more optical fibers; a transceiver configured to: receive a firstcontrol signal from the data source or the data sink by way of one ormore contacts of the first connector; generate a third modulated opticalsignal based on the first control signal for transmission to the secondconnector by way of the third set of one or more optical fibers; receivea fourth modulated optical signal from the second connector by way ofthe third set of one or more optical fibers; and generate a secondcontrol signal based on the fourth modulated optical signal forproviding to the data source or the data sink by way of the one or morecontacts of the first connector.
 21. The bidirectional datacommunications cable of claim 1, further comprising: a third set of oneor more optical fibers; a transceiver configured to: receive a firstcontrol signal from the data source or the data sink by way of one ormore contacts of the second connector; generate a third modulatedoptical signal based on the first control signal for transmission to thefirst connector by way of the third set of one or more optical fibers;receive a fourth modulated optical signal from the first connector byway of the third set of one or more optical fibers; and generate asecond control signal based on the fourth modulated optical signal forproviding to the data source or the data sink by way of the one or morecontacts of the second connector.
 22. The bidirectional datacommunications cable of claim 1, further comprising a cable housingincluding opposite ends mechanically coupled or attached to the firstand second connectors, respectively, wherein the cable housing at leastpartially encloses the first set of one or more fibers and the secondset of one or more fibers.